It has been disclosed in AU 532353 that bisphenolsulfone compounds of the formula ##STR2## wherein R is hydrogen, halogen, alkyl, cycloalkyl, aryl, aralkyl, hydroxy, alkoxy, aryloxy, carboxyl or carboalkoxy, m is an integer of 1 to 3, and when m is not less than 2, the groups represented by R may be the same or different and two of them, when adjacent to each other, may combinedly form a benzene ring, can be obtained by oxidation of the corresponding sulfoxide compounds or sulfone compounds using hydrogen peroxide in the presence of an alkali, and that said compounds are useful as light stabilizers, polyolefin modifiers, lubricants, additives, agrochemicals, and intermediates thereof. Further, it is described in Chemical Abstracts, 76, 25, 153267m that 4,4'-thiobis(6-cyclohexyl-2-methylphenol) is useful as a nonstaining stabilizer for polymers.
The above-mentioned Australian patent discloses 4,4'-diphenolsulfone, 4,4'-bis(2-tert-butyl-5-methylphenol)sulfone, 4,4'-bis(2-phenylphenol)sulfone, etc. as examples of 4,4'-bisphenolsulfone compounds, whereas no specific description can be found about alkyl-substituted cyclohexylphenol compounds. In addition, previously known 4,4'-thiobis(2-methyl-6-cyclohexylphenol) poses a problem that it colors polymers in actual use. It has not been known that these compounds exhibit biocidal action on wood destroying fungi.